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| author | Sergey Vojtovich <svoj@mariadb.org> | 2015-03-05 15:30:11 +0400 |
|---|---|---|
| committer | Sergey Vojtovich <svoj@mariadb.org> | 2015-03-05 15:30:11 +0400 |
| commit | e13459a11eb5938b54b88c7a1529491df6dd3b49 (patch) | |
| tree | c8cf642c9ab8b8620ba06cc3e131aadac766ba1e /storage/xtradb | |
| parent | 7dee7a036acfc0bcf7e6ab13a1556fde84714fd7 (diff) | |
| download | mariadb-git-e13459a11eb5938b54b88c7a1529491df6dd3b49.tar.gz | |
MDEV-7148 - Recurring: InnoDB: Failing assertion: !lock->recursive
Re-applied lost in the merge revision:
commit ed313e8a92a836422b9ae7b9ecf11c44ed4d5d66
Author: Sergey Vojtovich <svoj@mariadb.org>
Date: Mon Dec 1 14:58:29 2014 +0400
MDEV-7148 - Recurring: InnoDB: Failing assertion: !lock->recursive
On PPC64 high-loaded server may crash due to assertion failure in InnoDB
rwlocks code.
This happened because load order between "recursive" and "writer_thread"
wasn't properly enforced.
Diffstat (limited to 'storage/xtradb')
| -rw-r--r-- | storage/xtradb/include/sync0rw.ic | 7 | ||||
| -rw-r--r-- | storage/xtradb/sync/sync0rw.cc | 14 |
2 files changed, 14 insertions, 7 deletions
diff --git a/storage/xtradb/include/sync0rw.ic b/storage/xtradb/include/sync0rw.ic index 8aadc406132..d481d14009b 100644 --- a/storage/xtradb/include/sync0rw.ic +++ b/storage/xtradb/include/sync0rw.ic @@ -511,6 +511,7 @@ rw_lock_x_lock_func_nowait( ulint line) /*!< in: line where requested */ { ibool success; + ibool local_recursive= lock->recursive; #ifdef INNODB_RW_LOCKS_USE_ATOMICS success = os_compare_and_swap_lint(&lock->lock_word, X_LOCK_DECR, 0); @@ -525,10 +526,14 @@ rw_lock_x_lock_func_nowait( mutex_exit(&(lock->mutex)); #endif + /* Note: recursive must be loaded before writer_thread see + comment for rw_lock_set_writer_id_and_recursion_flag(). + To achieve this we load it before os_compare_and_swap_lint(), + which implies full memory barrier in current implementation. */ if (success) { rw_lock_set_writer_id_and_recursion_flag(lock, TRUE); - } else if (lock->recursive + } else if (local_recursive && os_thread_eq(lock->writer_thread, os_thread_get_curr_id())) { /* Relock: this lock_word modification is safe since no other diff --git a/storage/xtradb/sync/sync0rw.cc b/storage/xtradb/sync/sync0rw.cc index 3296e2e74a7..51bfba9950b 100644 --- a/storage/xtradb/sync/sync0rw.cc +++ b/storage/xtradb/sync/sync0rw.cc @@ -694,6 +694,8 @@ rw_lock_x_lock_low( const char* file_name,/*!< in: file name where lock requested */ ulint line) /*!< in: line where requested */ { + ibool local_recursive= lock->recursive; + if (rw_lock_lock_word_decr(lock, X_LOCK_DECR)) { /* lock->recursive also tells us if the writer_thread @@ -715,12 +717,12 @@ rw_lock_x_lock_low( } else { os_thread_id_t thread_id = os_thread_get_curr_id(); - if (!pass) { - os_rmb; - } - - /* Decrement failed: relock or failed lock */ - if (!pass && lock->recursive + /* Decrement failed: relock or failed lock + Note: recursive must be loaded before writer_thread see + comment for rw_lock_set_writer_id_and_recursion_flag(). + To achieve this we load it before rw_lock_lock_word_decr(), + which implies full memory barrier in current implementation. */ + if (!pass && local_recursive && os_thread_eq(lock->writer_thread, thread_id)) { /* Relock */ if (lock->lock_word == 0) { |